1. Field of the Invention
The present invention relates to storage systems of the type including tape cartridge storage facilities and associated virtual tape subsystems, and to methods of disaster recovery testing.
2. Background Art
A virtual storage system includes a tape cartridge storage facility accessible from a host through a virtual tape subsystem. Some virtual storage systems employ a second tape cartridge storage facility that maintains a backup data collection of the data collection at the first tape cartridge storage facility. Typically, the backup system is transparent to the user at the host, as is the virtual tape subsystem. The virtual tape subsystem is a system that emulates tapes and allows better utilization of tape volumes by providing virtual tape volumes and virtual tape drives. That is, the use of the virtual tape subsystem allows multiple tape volumes to be stored on a single tape cartridge at the storage facility.
Current implementations of tape cartridge storage facilities and associated virtual tape subsystems provide data redundancy to allow disaster recovery in the event of a disaster. Disaster recovery testing is conducted by simulating a disaster and then attempting to recover data. Currently, there is a demand for a significantly higher level of data availability for disaster recovery testing of the tape subsystems. Specifically, there is a need for production data to be available for disaster recovery testing while being currently available to production facilities within the same enclosed virtual environment. To meet this need requires concurrent access to the same data by two or more systems (production and disaster recovery systems), ability to modify data while preserving both the old and new copies of the data, and ability to use the same system facility identification on two or more systems.
For the foregoing reasons, there is a need for a method of disaster recovery testing with the backup data collection while continuing to maintain the production data collection and to maintain the backup data collection during testing.
It is, therefore, an object of the present invention to provide a method of disaster recovery testing with the backup data collection while continuing to maintain the production data collection and to maintain the backup data collection during testing.
In carrying out the above object, a method of disaster recovery testing is provided. The method is for use with a storage system including a first tape cartridge storage facility, a second tape cartridge storage facility, and a virtual tape subsystem. A standard control file contains information for managing the storage system. The first tape cartridge storage facility maintains a data collection. The second tape cartridge storage facility maintains a backup data collection. The method of disaster recovery testing with the backup data collection at the second tape cartridge storage facility while continuing to maintain the data collection and to maintain the backup data collection comprises creating a disaster recovery control file based on the standard control file. The method further comprises protecting an instance of the backup data collection, establishing a standard output pool, and establishing a disaster recovery output pool. The standard output pool is for recording changes to the backup data collection occurring under control of the standard control file after protecting the instance. The disaster recovery output pool is for recording changes to the backup data collection occurring under control of the disaster recovery control file after protecting the instance. The method further comprises conducting the disaster recovery testing under the control of the disaster recovery control file.
The method may further comprise reserving a portion of the virtual tape subsystem for exclusive use under control of the disaster recovery control file. The method may further comprise, after conducting the disaster recovery testing, terminating the disaster recovery testing. Thereafter, the protected instance of the backup data collection is unprotected and the portion of the virtual tape subsystem is unreserved. Preferably, the standard output pool and the disaster recovery output pool are at the second tape cartridge storage facility.
Further, in carrying out the present invention, a storage system is provided. The storage system includes a first tape cartridge storage facility, a second tape cartridge storage facility, and virtual tape subsystem. A standard control file contains information for managing the storage system. The first tape cartridge storage facility maintains a data collection, and the second tape cartridge storage facility maintains a backup data collection. The storage system further includes control logic executable to perform a method of disaster recovery testing with the backup data collection at the second tape cartridge storage facility while continuing to maintain the data collection and to maintain the backup data collection. The control logic is programmed to create a disaster recovery control file based on the standard control file. The control logic is further programmed to protect an instance of the backup data collection, establish a standard output pool, and establish a disaster recovery output pool. The standard output pool is for recording changes to the backup data collection occurring under control of the standard control file after protecting the instance. The disaster recovery output pool is for recording changes to the backup data collection occurring under control of the disaster recovery control file after protecting the instance. The control logic is further programmed to conduct the disaster recovery testing under control of the disaster recovery control file.
The system control logic may be further programmed to reserve a portion of the virtual tape subsystem for exclusive use under control of the disaster recovery control file. The control logic may further be programmed to, after testing, terminate the disaster recovery test, unprotect the protected instance of the backup data collection, and unreserve the portion of the virtual tape subsystem. In a preferred system, the standard output pool and the disaster recovery output pool are at the second tape cartridge storage facility.
The advantages associated with embodiments of the present are numerous. For example, embodiments of the present invention provide disaster recovery testing with the backup data collection at the second tape cartridge storage facility while continuing to maintain the data collection and to maintain the backup data collection by utilizing a disaster recovery control file, a backup instance, and separate output pools.
The above object and other objects, features, and advantages of the present invention are readily apparent from the following detailed description of the preferred embodiment when taken in connection with the accompanying drawings.